短語詞組短語bending g fatigue limit 彎曲疲勞極限bending stress fatigue limit 彎曲應(yīng)力疲勞極限alternating bending stress fatigue limit 交變彎曲應(yīng)力疲勞極限rotary bending fatigue limit 旋彎疲勞極限 返回 bending fatigue limit